The present invention relates in general to the connection and use of mobile computing devices with a fixed public network interface, and, more specifically, to obtaining a secure network connection using a fiber optic system.
Many people, such as travelers, are becoming increasingly reliant upon their mobile (i.e., portable) computing devices for many day-to-day tasks. Examples of portable computing devices include laptop computers and personal digital assistants (PDA's). Typical tasks include establishing and/or managing personal communications (e.g., telephone and electronic mail), conducting transactions (e.g., making reservations and paying by credit card), managing a schedule or calendar, monitoring financial information, and obtaining news and weather information, to name just a few.
When away from a home or office connection, it may often be desired to interface a personal portable device with a fixed outlet into a network such as 1) the public switched telephone network (PSTN) at a payphone or other telephone station to engage in a voice telephone call or 2) a computer data network (e.g., a wide area network, or WAN, connection to the Internet) at a public data terminal or kiosk to engage in computer networking applications such as e-mail. Use of such a fixed network outlet typically involves the use of personal, confidential information which may be transmitted from the personal computing device during use. For example, a phone card number and a personal identification number (PIN) or a credit card number may be used in establishing a pay telephone call (e.g., a long distance call). A private contact list may be consulted to determined a called telephone number. Computer network usernames and passwords may be accessed in launching the desired computer network applications.
The privacy of personal information transmitted by the portable computing devices may be compromised by thieves who actively attempt to obtain the information using various kinds of surveillance and eavesdropping. For example, when information from a PDA or a traditional telephone calling card such as a telephone card number and PIN are entered manually on a telephone keypad, thieves have been known to videotape the keypad entries.
A wireless RF link between a portable device and a fixed station can avoid the visible display of personal information that might be videotaped, but the RF communication signals radiate throughout an uncontrolled area around the device and are subject to being intercepted by thieves. The RF signals can be encrypted, but that requires coordination (e.g., exchange of secret keys) between the sender and receiver, which is often not practical for a public network outlet that is intended to provide service to any requesting device. In this situation, the encryption keys would have to be exchanged in the same unsecured manner and could be intercepted and used by the information thieves using a “man in the middle” ploy or other techniques.
Both PDA's and laptop computers are typically provided with an infrared (IR) beaming port for achieving serial communication using one of the IrDA standards of the Infrared Data Association. The IR beam for such a beaming operation spreads over a defined angular region to ensure that the desired receiver is illuminated by the IR beam. However, there is substantial spillage beyond the intended receiver which makes it possible for thieves to intercept the transmitted data when used in a public place.